Snowplow



Aug. 13, 1957 s. P. BEVAN 2,302,237

SNOWPLOW Filed Aug. 24, 1953 3 Sheets-Sheet 1 vil .l j,,

- INVENTOR.

P. Bevan Aug. 13, 1957 G. P. BEVAN 2,802,287

SNOWPLOW Filed Aug. 24, 1953' v s Sheets-Sheet 2 Jill!!! INVENTOR. F g.4. BY 6 G. P. BEVAN Aug. 13, 1957 SNOWPLOW s Shets-Sheet 5 Filed Aug. 24, 1953 1 INVENTOR. filen P. Bevan United States Patent.

This invention relates to snow plows and more particularly to snow plows of the rotary type.

In snow plows of the so-called rotary type, considerable difiiculty has been experienced in delivering the snow discharged from the plow in a substantially solid stream at a distance from one side of the plow. In previous plows, while part of the discharged snow is thrown 'well to one side of the plow, a large'percentage of the snow is distributed more or less uniformly between the plow and the extreme end of the stream of snow. This is of no great concern where the plow is clearing a relatively narrow highway, but in the case of airports and similar large fields which are to be cleared, it necessitates picking up snow which has already been moved to some extent and throwing it further toward the edge of the field from which the snow is being removed.

The principal object of the invention is to provide a rotary snow plow of much greater etficiency than previous plows, particularly in its handling of large quantities of snow with a minimum of clogging, and in discharging the snow in a clean cut concentrated stream at a relatively great distance to the side of the plow.

Another object is to provide a novel means for changing the direction of the stream of snow discharged from the plow.

These objects are attained in part by means of a novel rotary thrower of the axial inlet tangential outlet type, the casing. of which is rotatably mounted and in which the blades are of generally arcuate or U-shaped crosssection. They are also attained in part by providing what may be termed an annular screw conveyor which consists of a plurality of vanes surrounding the inlet and extending forwardly and ciroumferentially of the impeller. They are also attained in part by means of a bafile plate of substantially the same size as the opening in the thrower spaced forwardly of the inlet opening and between the front and rear ends of the vanes of the screw conveyor.

By means of this novel construction packed snow is broken up and aerated so that it can be efiiciently discharged at one side or other of the surface being plowed and at a substantial distance therefrom, with little snow falling between the plow and the end of the thrown stream of snow.

The principal reason for the highly successful operation of the thrower is that by means of the novel construction the snow is entrained in a stream of air and blown out of the thrower. Rotary snow plows operate upon the principle that the snow itself should be moved with whatever air contained therein being purely incidental. In other words, the present invention moves air at high velocity and carries with it snow entrained in the air stream instead of moving snow directly.

In the drawings:

Figure l is a front view of a mold board and housing for a screw conveyor at the front of a snow plow and showing the novel thrower located relative to the housing;

Figure 2 is a front view of the thrower casing with the impeller removed;

Patented Aug. 13, 1957 Figure 3 is a fragmentary perspective view of the casing;

Figure 4 is a fragmentary cross-sectional view taken on substantially the line 44 of Figure 3;

Figure 5 is a front elevational view of the impeller;

Figure 6 is a perspective view of the impeller; and

Figure 7 is a perspective view of the impeller taken from the side thereof.

The thrower shown in the drawings may form a part of a snow plow with which a rotary conveyor placed transversely in front of the thrower is used. Figure l is a front view of a moldboard and housing 10 for such conveyor showing the location of the thrower, which is indicated in its entirety by numeral 11. The rear wall 12 of the housing 10 has a circular opening 13 therein behind which the thrower is located.

The impeller is shown outside of its housing in Figures 5 to 7. It comprises "a rear circular wall 14 and av front annular wall 15 having a central inlet opening 16. These walls are spaced apart axially by means of blades 17 and braces 18. The blades are of arcuate cross-section with the concave side facing the direction of rotation of the impeller. The radial dimensions of the bladesare the same as that between the inner and outer circumferences of the annular front Wall 15.

Mounted on the front face of front wall 15 are a plurality of vanes19 which extend forwardly and cir-' cumferentially of the impeller. These vanes are fashioned so that their outer and inner diameters are no greater than the outer and inner diameters of the annular front wall 15. See Fig. '5.

The vanes are braced by means of plates 20 welded to the vanes at right angles thereto and gussets 21. The plates.20 not only brace the vanes 19 but aid in breaking up and feeding snow to the interior of the thrower. The thrower will operate satisfactorily, however, without blades 20.

Fastened to the inner edge of the vanes 19 approximately midway between the front and rear ends thereof is a bafile plate 22 of substantially the same diameter as the aperture 16 in the front annular wall l5.

It will be evident that because of the forward and circumferential positioning of the vanes 19 they will chew into snow gathered in the housing 10 and convey it into the inlet opening of the thrower. Bafile plate 22, however, prevents snow from entering too rapidly and clogging the thrower. Snow must be carried in by the vanes and they are designed to move not more than the capacity of the thrower.

The impeller is mounted on a shaft 23 extending through and fastened to the rear wall 14 and baffie plate 22. It is mounted in front and rear bearings 24 and 25. The latter is mounted on the rear wall of the thrower casing which will be described presently. The front bearing is carried by brackets 26 attached to the rear wall of the housing 10, or to other framework of the plow.

The impeller is contained within a casing shown in Figs. 2 and 3. The casing comprises a rear wall 27 of circular shape, only a portion of which is shown in Figure 4. It has a forwardly extending perimetral flange 28. A metal rod 29 surrounds the flange 28 and is welded thereto. The rod forms a bearing for circumferential wall 30 of the casing. The latter is in the form of a cylindrical hoop, but is provided with a discharge spout 31. The rear end of the wall 30 has a metal rod 32 welded internally thereof which, in conjunction with rod 29, acts as a stop to hold wall 30 on wall 27, yet

permits wall 30 to be rotated.

Extending forwardly from wall 30 is a tubular extension which surrounds the vanes 19 and whose front end is located in juxtaposition to the rear wall 12 of the housing 10 surrounding the opening 13 therein.

The cylindrical wall 30 of the thrower casing can be rotated n the bearing 29 by any suitable mechanism. A simple form of rotating device consists of a cable 33 attached at its ends to wall 30 at 34 and 35. The intermediate portion is wrapped around a drum 36 which can be rotatedby a crank 37 or other source of power. In that way the spout 31 can be moved to throw snow in either direction.

The impeller is driven by means of any suitable prime mover coupled to shaft 23 and mounted on the frame of the plow rearwardly of the housing 10. The impeller is capable of high speed rotation and because of the arrangement of vanes which break up and aerate the snow and pull it into the impeller, the snow can be thrown comparatively great distances. Furthermore, the battle plate in front of the impeller eliminates clogging of the thrower. It also forces air entering the thrower to pass between the vanes in the same path as the snow, thus effectively aiding the flow of snow through the impeller.

The scope of the invention is indicated in the appended claims.

I claim:

1. In a snow plow, a centrifugal thrower of the axial inlet, tangential discharge type, comprising a rotary impeller and a casing for said impeller, said casing having a circumferential wall'surrounding said impeller and having a discharge opening therein, said casing having a closed rear wall and being open at the front, said impeller including a back wall and an annular front wall having a large central opening therein and a plurality of substantially radial blades located between and connected to said walls, said radial blades being spaced outwardly of the inner edge of said annular front wall, and a baffle plate of substantially the same size as the opening in the front wall of the impeller located forwardly of the front wall and in registry with the opening therein.

2. A rotary thrower for a snow plow comprising a cylindrical casing, said casing comprising a cylindrical casing, said casing comprising a closed back wall, a generally cylindrical circumferential wall having one end connected to said back wall, said circumferential wall being open at the front, an impeller rotatably mounted in said casing, said impeller comprising a back wall and an annular front wall having a large central opening therein, and a plurality of radial blades connected to said walls and located therebetween, and a plurality of vanes attached to said front wall forwardly thereof and extending forwardly and circumferentially in the direction of rotation of said impeller, the radially inner edges of said vanes being located radially outwardly of the opening in the front wall.

3. A rotary thrower of the character defined in claim 2 wherein a bafiie plate of substantially the same diameter as the aperture in the front wall of the impeller is attached to the inner edges of said vanes parallel to the front wall of the impeller and intermediate the ends of said vanes. 1

4. A rotary thrower of the character defined in claim 2 wherein said vanes are provided with reinforcing blades fixed to the rear surfaces thereof and extending toward the front wall of the impeller but terminating short of said front wall.

5. A rotary thrower of the character defined in claim 2 wherein the circumferential wall is rotatably mounted on the back wall of the casing whereby to permit variation of the position of the discharge opening in said circumferential wall.

References Cited in the file of this patent UNITED STATES PATENTS 405,300 Caldwell June 18, 1889 1,570,806 Walling Jan. 26, 1926 1,603,978 Parkhurst Oct. 19, 1926 1,987,313 Severson Jan. 8, 1935 2,171,056 Clay Aug. 29, 1939 2,605,561 Maynard et a1. Aug. 5, 1952 2,650,439 Hickman Sept. 1, 1953 FOREIGN PATENTS 642,058 Germany Feb. 20, 1937 

